JPH0260094B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, a load section is controlled to open and close by an electronic control section, has a terminal for supplying power to the load section and the control section, and a first accumulator is connected via a rectifier in a stationary state. is charged, and when this first accumulator starts load operation by actuation of a pushbutton with a switching function, a second accumulator supplying power to the control unit is connected to a recharging branch line with a current limiting resistor. The present invention relates to an electronic time switch which supplies power to a load section and a control section by charging via the electronic time switch, and which turns on a load to which an alternating current voltage is supplied for a limited time.

This type of time switch has a load section which is controlled to open and close by an electronic control section in order to turn on a load, such as a lamp, to which an alternating current voltage is supplied for a limited time. A first accumulator is charged via the rectifier in the resting state, and this first accumulator
When starting load operation by actuating a pushbutton with a switching function, the second accumulator supplying power to the control unit is charged via a recharging branch line with a current-limiting resistor, thereby recharging the load. The unit and the control unit are supplied with power from two terminals. Such a time switch has already been proposed (Japanese Unexamined Patent Publication No.
57-170426).

In the time switch mentioned at the beginning, only two lead wires are required, whereas in the conventional electronic time switch, a lead wire for turning on the load, a lead wire for supplying current to the electronic control section, That is, two or more lead wires (often four lead wires) are required in total. Therefore,
This type of time switch can be easily replaced with a wiring switch in an existing wiring box. The operating time of the load to be turned on can be adjusted in the above-mentioned time switch by means of a timing element. This timing element is connected in parallel to the second accumulator and consists of a series connection of a fixed resistor and a variable resistor. When such a time switch is manually turned on, the load (for example a lamp) in the load section is operated for a fixed preset time.

An object of the present invention is to make it possible to individually adjust the load application time in each case by varying the length of operation time of the operation button in the time switch mentioned at the beginning. .

This object is achieved according to the invention in the electronic time switch mentioned at the outset in that the recharging branch with current-limiting resistor has a parallel connection of an ohmic resistor and a threshold-operated valve.

Regarding the time switch described above, the adjustment potentiometer consisting of a fixed resistor and a variable resistor is no longer required; instead, the recharging branch with a current limiting resistor has an ohmic resistor and a threshold operated valve in parallel. A parallel connection body configured to be connected is provided. In the cut-off state, the first accumulator is charged. When the pushbutton is actuated, the second accumulator is charged via a current-limiting resistor and a threshold-operated valve (for example a Zener diode). 1st
If the potential difference between the accumulator and the second accumulator drops below the threshold of the forward-inserted threshold-operated valve, and if the pushbutton is kept pressed further, the current-limiting resistor and the parallel connection ohm Recharging from the first accumulator to the second accumulator continues via both resistors. Depending on the different charging times of the second accumulator, the closing time of the time switch is determined. Note that this type of time switch can also be operated again during driving.

When the ratio of the capacity of the first accumulator to the capacity of the second accumulator is 2 to 6, practically good charging characteristics can be obtained. It is particularly advantageous to select the capacity of each accumulator such that the ratio between the capacity of the first accumulator and the capacity of the second accumulator is between 3 and 5. To protect the pushbutton contacts, if the current limiting resistor is set to a practical size, the minimum You can get input time. A relatively large time constant, such as that caused by the capacitance of the second accumulator and the resistance of the parallel connection, prolongs the minimum time.

Next, the present invention will be explained in detail based on an embodiment schematically shown in the drawings.

FIG. 1 shows the electrical configuration of the time switch. Connected to the terminals 1 and 2 are two lead wires 3 leading to a load 4 supplied with power by a power source 5. In this embodiment, terminal 1 is connected via a protective fuse 6 to a rectifier 7, which
is configured as a full-wave rectifier. The terminals 1, 2 of the load section with the power valve 8 also supply power to the control section at the same time. For this purpose, in the standstill state, the first accumulator 9 is charged via the rectifier 7;
The accumulator 9 charges the second accumulator 11 when put into load operation by means of a pushbutton 10 with a switching function. The second accumulator 11 then supplies power to the control unit.

Terminals 1, 2 are connected to a rectifier 7 in the embodiment shown in FIG. In this embodiment, the rectifier 7 is constructed as a full-wave rectifier without a smoothing circuit. An electronic power valve 8 is connected to the rectifier output circuit of the rectifier 7 , and its control input terminal 12 is connected to one output terminal 13 of an electronic control valve 14 .
The power valve 8 can in particular be constructed as a thyristor. The other output 19 of the control valve 14 , i.e. the one not connected to the control input 12 of the power valve 8 , is connected to a conductor 16 with a capacitor 15 .
The first branch line 21 of the rectifier output circuit is connected to the first branch line 21 of the rectifier output circuit. Control valve 14 is connected at its control input 17 to second accumulator 11 .

The second branch line 22 of the rectified output circuit is connected to the power valve 8
The power valve 8 is connected to the output terminal 20 of the power valve 8 , and is also connected to the control input terminal 12 of the power valve 8 via a resistor 23 . This second branch line 22 further includes a control valve 14.
is at its output 19 and the second accumulator 1
1 and a first accumulator 9 are connected. The accumulators 9, 11 are constructed as capacitors in this exemplary embodiment.

In the embodiment of FIG. 1, the control valve 14 is
It is configured as a MOS field effect transistor (MOS-FET). Between the second branch line 22 and the output end 19 of the control valve 14 to which the control input end 12 of the power valve 8 is not connected, there is a Zener diode 24 and a capacitor placed in parallel thereto. 25 are connected. The Zener diode 24 and the capacitor 25 are designed to protect the MOS-FET from overvoltage and to assist in the blocking characteristics of the MOS-FET.

The first branch 21 of the rectifier output circuit is connected to the pushbutton 10 in this embodiment via a resistor 26 and a diode 27 inserted in the forward direction. Here, a resistor 26 separates the load section from the control section, and a diode 27 prevents the first accumulator 9 from discharging in the closed state of the time switch.

The pushbutton 10 forms a conductive path from the diode 27 to the first accumulator 9 in the rest state;
The first accumulator 9 is then connected to a permanent contact 30 . A contact 32, which is switched from the contact 31 to form a conductive path in the closed state, is connected to the second accumulator 11 via a resistor 33 on the control input end 17 side of the control valve 14.

Between the two branch lines 21, 22 of the rectifier output circuit, a threshold-operated switch, in this example a Zener diode 34, is connected in parallel to the series connection of the pushbutton 10 and the first accumulator 9.
This Zener diode 34 is connected to the first accumulator 9
When the battery is charged to a certain specified voltage value, push button 1 is pressed.
This helps ensure that it remains in its charged state as long as 0 remains unpressed.

In the commercially available wiring switch shown in FIG. 2, the manual operation mechanism 40 is configured as a push button, and a base plate 42 can be disposed within the base 41 of the switch. circuit components and wiring conductors are installed.

The time switch described above operates as follows.

In the cut-off state, the rectifier 7 rectifies the applied voltage. The first storage 9 is charged via the resistor 26 and the diode 27 to a voltage value corresponding to the Zener voltage of the Zener diode 34 .

The control valve (MOS-FET) 14 is then off, and the control input 12 of the power valve (thyristor here) 8 is at reference potential 0 via the resistor 23.
In that case, the power valve 8 is non-conducting. When the pushbutton 10 is actuated, a portion of the charge in the accumulator 9 flows into the accumulator 11 via a current limiting resistor 33 for contact protection and a threshold-operated valve (for example a Zener diode) 44. The control valve 14 has a control input end 17
It turns on when a positive voltage is applied to it. Due to the ripple in the rectified output voltage of the rectifier 7, a current flows through the capacitor 15, the control valve 14 and the resistor 23. At that time, a voltage drop occurs across the resistor 23, which turns on the power valve 8. This time switch is thus turned on and the load (for example a lamp) 4 is supplied with voltage. If the potential difference between the first accumulator 9 and the second accumulator 11 drops below a certain threshold (at which threshold the threshold-operated valve 44 is still on), the pushbutton 10 is not operated. If it is longer, the second accumulator 11
can be subsequently charged via the parallel resistor 43. Thereby, the time required to turn on the time switch can be set to an appropriate length.

When the voltage at the control input 17 of the control valve 14 falls below a certain specified value, the control valve turns off and the power valve 8
The control input terminal 12 of is set to the reference potential 0. The power valve 8 becomes non-conducting and the time switch returns to its resting state again. Since the current circuit is interrupted, the load, for example the lamp 4, is no longer supplied with power.

The operating time can be extended by operating the time switch again. This is possible until sufficient charge from the first accumulator 9 to the second accumulator 11 cannot be recharged. Therefore, the time switch is surely shut off. In the closing state, the diode 27 prevents the first accumulator 9 from discharging via the power valve 8 .

If the ratio between the capacity of the first accumulator and the capacity of the second accumulator is between 3 and 5, then if the push button 10 is operated for 2 seconds, a closing time of approximately 4 to 5 minutes will be obtained. , and if the operation time of the push button 10 is set to 6 seconds, a charging time of 5 to 6 minutes can be obtained.

Protective fuse 6 protects rectifier 7 and power valve 8 from overloads and short circuits.

[Brief explanation of drawings]

Fig. 1 is a circuit connection diagram showing one embodiment of an electronic time switch according to the present invention, and Fig. 2 shows a wiring switch configured as a time switch by attaching a base plate equipped with the circuit shown in Fig. 1. It is a side view of an example. 1, 2...terminal, 4...load (lamp), 7...rectifier, 8...power valve, 9...first accumulator, 10...push button, 11...second accumulator, 14...control valve, 3
3... Current limiting resistor, 43... Ohm resistor, 44... Threshold operation valve (Zener diode).

Claims (1)

[Claims] 1. The load section is controlled to open and close by an electronic control section, and has a terminal for feeding power to the load section and the control section,
A first accumulator is charged via a rectifier in a stationary state, and when this first accumulator starts load operation by operating a push button with a switching function, a second accumulator supplies power to the control unit. In an electronic time switch, the load section and the control section are supplied with power by charging the device via a recharging branch line having a current-limiting resistor, and the load supplied with an alternating current voltage is switched on in a time-limited manner. An electronic time switch characterized in that said recharging branch line has a parallel connection consisting of an ohmic resistor and a threshold operated valve. 2. The electronic time switch according to claim 1, wherein the ratio of the capacity of the first accumulator to the capacity of the second accumulator is 2 to 6. 3. The electronic time switch according to claim 2, wherein the ratio of the capacity of the first accumulator to the capacity of the second accumulator is 3 to 5.